Management of the
woman with threatened birth of an infant of extremely low gestational age Management of the
woman with threatened birth of an infant of extremely low gestational age A Joint Statement with the Society of Obstetricians and Gynaecologists of Canada
Fetus and Newborn Committee, Canadian Paediatric
Society (CPS)
Maternal-Fetal Medicine Committee, Society of
Obstetricians and Gynaecologists of Canada
Approved by the CPS Board of Directors in 1994
Canadian Medical Association Journal 1994; 151(5): 547-551, 553
Reference No. FN94-01
Revision in progress February 2009
Index of position statements from the Fetus and Newborn Committee
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Contents
Objective: To offer guidelines for parents, physicians and other members of the
health-care team for management of the probable birth of an infant with a gestational age
of 26 completed weeks or less.
Options: Vaginal birth or birth by cesarean section for fetal indications and
active treatment or palliative care of the infant at birth.
Outcomes: Increased risk of complications for the mother from cesarean section at
this stage of pregnancy and the difficulty in making a prognosis before or at birth for an
infant of this gestational age.
Evidence: Published survival rates and risks of impairment or disability for
infants of each gestational age; current information provided by directors of follow-up
clinics in Canadian university-based pediatric programs.
Values: The recommended management of the woman and her fetus or infant is based on
many underlying considerations, including the best interests of the mother and her infant
and the views of fully informed parents.
Benefits, harms and costs: Use of these guidelines will enable health care
providers to offer parents of infants of extremely low gestational age therapeutic choices
before birth based on full information on likely outcomes, to avoid unnecessary cesarean
section and to minimize suffering when treatment of infants is not in their best
interests.
Recommendations: According to current Canadian outcome data, fetuses with a
gestational age of less than 22 completed weeks are not viable and those with an age of 22
weeks rarely viable. Their mothers are not, therefore, candidates for cesarean section,
and the newborns should be provided with compassionate care, rather than active treatment.
The outcomes for infants with a gestational age of 23 to 24 completed weeks vary greatly.
Careful consideration should be given to the limited benefits for the infant and potential
harms of cesarean section, as well as to the expected results of resuscitation at birth.
Cesarean section, when indicated, and any required neonatal treatment are recommended for
infants with gestational ages of 25 and 26 completed weeks; most infants of this age will
survive, and most survivors will not be severely disabled. Treatment of all infants with a
gestational age of 22 to 26 weeks should be tailored to the infant and family and should
involve fully informed parents.
Validation: Members of the Fetus and Newborn Committee of the Canadian Paediatric
Society (CPS) were involved in the preparation of this article, which was reviewed and
modified by the Ethics Committee of the CPS and the Maternal-Fetal Medicine Committee of
the Society of Obstetricians and Gynaecologists of Canada (SOGC). A draft was circulated
to Canadian university-based perinatal programs and members of the Section on
Neonatal-Perinatal Medicine of the CPS. Comments from physicians and bioethicists were
incorporated, when possible, into the final version. There are no similar guidelines in
North America.
Sponsors: These guidelines were sponsored and endorsed by the CPS and the SOGC.
This article offers guidance to parents, physicians and other members of the health care team facing the probable birth of an infant of extremely low gestational age: 22 to 26 completed weeks. Although the prevalence of such births is very low, slightly less than 2 per 1000 births,1 the effect on the infant and parents is profound. Recent advances in treatment have increased survival rates for infants born at this stage of gestation. In addition, the death rate decreases rapidly with each week of gestation.2-5 A recent decrease in the prevalence of impairment and disabilities in surviving infants has also been reported;6-10 however, the rate of reduction has lagged behind that of the mortality rate. Consequently, the number of infants with impairments or disabilities may be increased, but the increase in the number of neurologically intact survivors is even greater.
Early-gestation birth is attended by extraordinarily complex and difficult ethical decisions. All of the ethical principles come into play in determining what is best for the mother and her infant. At 22 weeks' gestation, autonomy of the mother and physician nonmaleficence and beneficence toward her are paramount considerations in treatment decisions. As pregnancy progresses, concern for the life and health of the fetus or infant rapidly increases. Distributive justice considerations may complicate the physician's concern for an infant and family: although there are few infants of extremely low gestational age, care of these infants requires very great use of the resources of a neonatal intensive care unit (NICU), and resource use escalates rapidly the lower the gestational age.11,12 Hence, physicians' concerns are complicated by pressures to distribute equitably the limited health care resources.
In the following discussion we use the definition of gestational age in the International Classification of Disease (ICD-10).13 For clarity, gestational age is expressed in completed days and weeks. For example, the period 22 weeks and 0 days to 22 weeks and 6 days (154 days to 160 days inclusive) of gestation is referred to as "22 completed weeks."
The birth of a child of a gestational age of 22 to 26 completed weeks is fraught with uncertainty concerning the chance of survival and the risk of impairment and disability. Although survival and disability rates are of some help, it is often impossible to make a prognosis before birth. Accurate prognosis, especially of long-term outcome, is almost as difficult in the first few days after birth. This uncertainty may cause extreme stress for parents and caregivers around the time of the birth and during the neonatal period. Moreover, despite the use of pain control, the pain and suffering experienced by the infant in intensive care cannot be determined.
Twins and other multiple fetuses are overrepresented in early-gestational birth; they face higher disability and death rates than singletons of a comparable gestational age.14 The number of multiple births has increased in recent years because of in-vitro fertilization and hormonal stimulation of ovulation.
Because gestational age is sometimes unknown or inaccurate, most data on deaths and disabilities in early-gestation infants are given by birth weight. However, other than an estimate from ultrasonographic examination, fetal weight is unavailable to obstetricians and neonatologists before birth. Therefore, our guidelines for management are based on gestational age in completed weeks, although we recognize that this may be inaccurate. The guidelines provide a way to balance ethical considerations concerning, on the one hand, the short-term and long-term risks of death and disability in fetuses and infants and, on the other, the emotional and physical burdens such premature births place on parents. We also give some guidance to physicians confronted with the difficult decision to start or withhold treatment of such infants at birth. This article does not address later management in the NICU. Such management should be guided by an earlier statement by the Canadian Paediatric Society.15
Drafts of these guidelines were distributed to staff of all Canadian university tertiary perinatal centres, members of the Section on Neonatal-Perinatal Medicine of the Canadian Paediatric Society, several bioethicists and other physicians, who reviewed them and provided input. Practice in this difficult area of perinatal care varies; these guidelines were written with these differences in mind. We emphasize the need for joint decision making with fully informed parents. These guidelines have been approved by the Canadian Paediatric Society and the Society of Obstetricians and Gynaecologists of Canada.
The preferred management of a woman with a threatened birth of an infant of this gestational age is consultation with a perinatologist in a tertiary care centre followed, if appropriate, by admission to the centre.
Ideally, the management of a woman at risk of giving birth at this stage of pregnancy should be multidisciplinary and unified. The skills and knowledge of specialists in maternal-fetal medicine and neonatology should be combined and complemented by the expertise and involvement of nurses, social workers and other professionals.
The best available assessment of fetal health status, gestational age and weight, and information concerning the short-term and long-term risks and benefits of outcomes for the mother, fetus and infant are needed to make recommendations for management.
The following information should be given to the parents and should form the basis of such recommendations:
Plans for management should be based on reasonable expectations and should respect the wishes of the parents, the best interests of the infant and the recommendations of the health care team. If the parents and health care team do not agree, differences can usually be resolved through further discussion with other professionals (e.g., the hospital ethics committee), if necessary and as time allows.
Planned collaborative decision making may be limited as the result of an unanticipated premature birth or a serious illness in the mother or fetus.
Management plans discussed with parents should be flexible in regard to starting, withholding or withdrawing treatment; these plans may need to be changed at birth or afterward, depending on the status of the infant.
A neonatologist or delegate should attend births of infants of this gestational age to help with treatment decisions based on the condition of the infant.
Whenever possible, a decision to withhold or withdraw treatment immediately after birth should be made jointly, through full discussion, by the physician, the parents and appropriate members of the health care team. Decisions should be clearly documented in the medical record.
In all cases the infant should be given compassionate care, including warmth and pain relief required for comfort.
Programs for the management of births of infants of an extremely low gestational age should include suitable clinical audits of perinatal death and disability, including the long-term outcome for surviving infants. In addition, such programs should hold regular courses in conjunction with hospitals in their catchment areas to inform staff of advances in care.
Menstrual history, corroborated by the results of an ultrasonographic examination, provides the best estimate of gestational age.16 Complete antenatal records, including the results of a first-trimester pelvic examination, previous ultrasonographic examinations and measurements of symphysis-fundus height, should be consulted.
If gestational age is unknown, it can be estimated adequately from the results of ultrasonographic examinations. Prediction of gestational age from ultrasonography is reported to be accurate to within 8 days in the first trimester and 20 days in the second trimester.17
An ultrasonographic examination to determine the biometric and morphologic features and weight of the fetus should precede discussions concerning the management of the birth if time permits. Estimates of fetal weight obtained from ultrasonographic examinations vary within 10% to 15% of the true weight, depending on the amount of amniotic fluid, fetal presentation and lie, biometric indices used to calculate weight and the expertise of the estimator.18 Table 1 gives approximate mean birth weights for infants with gestational ages from 22 to 26 completed weeks.13
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As part of the ultrasonographic examination for fetal biometry, clinicians should make a careful search for congenital anomalies. Any maternal or fetal risk factors for growth restriction should be considered in interpreting an estimate of fetal weight.
Many physicians have requested information and guidance about referring woman with a threatened birth of an early-gestation infant and about starting or withholding treatment of infants of specific gestational ages. Such guidance must be general because data on outcomes are changing; in any particular centre outcomes will be influenced by numerous factors. Moreover, although parents may insist on treatment when first confronted with the likelihood of a very premature birth, they may hold less definite opinions after they understand the implications of a birth at the extreme limits of viability.
These guidelines summarize practices in Canadian perinatal centres and outcomes from these centres. Published outcome data have been supplemented with unpublished information obtained from the directors of follow-up clinics in seven Canadian university-based tertiary care programs (Drs. Edmond Kelly, Mount Sinai Hospital, Toronto, Ont.; Marie Kim, St. Joseph's Health Centre, London, Ont.; Charlene Robertson, Royal Alexandra Hospital, Edmonton, Alta.; Saroj Saigal, Chedoke-McMaster Hospitals, Hamilton, Ont.; Reginald Sauvé, Foothills Hospital, Calgary, Alta.; Michael Vincer, Grace Maternity Hospital, Halifax, NS; and Michael Whitfield, British Columbia's Children's Hospital, Vancouver, BC: unpublished data, 1993).
Parents should be informed that the statistics provided to them by the centre are retrospective and based on small numbers; however, they are the best evidence available. As we noted earlier, whenever possible the data on outcomes should be specific to the perinatal centre. As well, parents need to be informed that the treatment offered by the perinatal team is tailored to their needs and the needs of their infant.
Infants
with a gestational age of less than 22 completed weeks (154 days)
Treatment decisions should be based on the health of the mother. At this stage of
gestation the fetus is not viable; therefore, cesarean section provides no benefit to the
fetus and should be performed only if indicated for the mother's health.
Since infants of this gestational age cannot be expected to survive, they should be given only compassionate palliative care. However, the neonatologist may decide to provide active treatment for apparently viable infants whose gestational age may have been underestimated.
Infants
with a gestational age of 22 completed weeks (154 to 160 days)
Although very infrequent, the survival of such infants is reported; it depends partly
on individual variations in physiologic maturity. Accounts of survival at this gestational
age are mainly anecdotal, and so data on disability in survivors are limited.
Treatment decisions should be based primarily on the health of the mother. Because the mother would be subjected to unjustifiable risk, cesarean section should not be performed except when it is indicated for the mother's health. Women requesting cesarean section for an infant of this gestational age should, if at all possible, be dissuaded.
Because so few infants born at this gestational age are expected to live, most can be offered only compassionate palliative care. Active treatment should be started only at the request of fully informed parents or if it appears that the gestational age has been underestimated.
Infants
with a gestational age of 23 to 24 completed weeks (161 to 174 days)
Infants born at just 23 weeks may have very different prognoses from those born at
almost 25 weeks. Reported neonatal survival rates increase rapidly within this 2-week
interval, varying from 10% to 50%.2-5,19-21
Among surviving infants 20% to 35% have disabilities such as cerebral palsy, hydrocephalus, severe cognitive deficit, blindness, or deafness, or a combination of these.6,9-11 Although most disabilities22 in these infants are mild or moderately severe,6-9 up to 10% are severe and necessitate significant caretaking, far beyond that usually required by infants of their age.9
In cases of fetal distress cesarean section is rarely performed, owing to the high rates of infant mortality and to the risk of adverse outcomes in subsequent pregnancies resulting from the types of uterine incision used. Exceptions are more appropriate in infants with gestational ages approaching 25 weeks. Informed parents may wish to override the obstetrician's opinion that a cesarean section should not be performed. In such cases, a second consultation may be obtained and care of the mother transferred to a colleague without prejudice.
The initial management of an infant of this age should be consistent with the parents' wishes. For most of such infants without fatal congenital anomalies management may include resuscitation. However, clinicians should discuss with the parents the need for flexibility in deciding to start or withhold resuscitation, depending on the infant's condition at birth.
Infants
with a gestational age of 25 to 26 completed weeks (175 to 188 days)
Survival rates for infants of this gestational age are currently 50% to 80%.2,3,5,20,21 Impairments and disabilities22 such as those previously described affect 10% to 25% of
these infants.6,9
Decisions concerning the mode of delivery should be based on the best interests of the mother and infant. Cesarean section is the accepted mode if the fetus is compromised during labour. If the parents initially refuse a cesarean section the clinician must confirm that the parents fully understand the implications and likely outcomes of their decision.
In addition, resuscitation should be attempted for all infants of this gestational age without fatal anomalies.
These guidelines were sponsored and endorsed by the Canadian Paediatric Society and the Society of Obstetricians and Gynaecologists of Canada. We thank Mrs. Laurie Dawe for secretarial support.
Members:
Drs. Alexander C. Allen (chairman), head, Department of Neonatal Pediatrics, Grace
Maternity Hospital, Halifax, NS; Barbara A. Bulleid, director of nurseries, Dr. Everett
Chalmers Hospital, Fredericton, NB; Douglas D. McMillan (cochairman), chief, Division of
Neonatology, Foothills Hospital, Calgary, Alta.; Thérèse Perreault, neonatologist,
Montreal Children's Hospital, Montreal, Que.: and C. Robin Walker, chief, Division of
Neonatology, Children's Hospital of Eastern Ontario, Ottawa, Ont.
Consultants: Drs. Graham W. Chance, chief, Division of Neonatal-Perinatal Medicine, St.
Joseph's Health Centre, London, Ont.; Eugene W. Outerbridge, Division of Newborn Medicine,
Montreal Children's Hospital, Montreal, Que.; and Saroj Saigal, director of Growth and
Development Clinic, Chedoke-McMaster Hospitals, Hamilton, Ont.
Liaisons: Drs.
Philip G. Banister, Senior medical consultant, Maternal and Child Health, Health Canada,
Ottawa, Ont.; Renato Natale, chairman, Maternal-Fetal Medicine Committee, Society of
Obstetricians and Gynaecologists of Canada, and chief, Department of Obstetrics and
Gynaecology, St. Joseph's Health Centre, London, Ont.; Jacques Saintonge, past chairman,
Section on Neonatal-Perinatal Medicine, Canadian Paediatric Society (CPS), and
neonatologist-in-chief Hôpital Maisonneuve-Rosemont, Montreal, Que.; Apostolos
Papageorgiou, chairman, Section on Neonatal-Perinatal Medicine, CPS, and
neonatologist-in-chief, Jewish General Hospital, Montreal, Que.; and Gerald B. Merenstein,
chairman, Committee on Fetus and Newborn, American Academy of Pediatrics, and
vice-chairman of academic affairs, Department of Pediatrics, University of Colorado,
Denver.
Principal author: Dr. Graham W. Chance, chief, Division of Neonatal-Perinatal Medicine, St.
Joseph's Health Centre, London, Ont.
Maternal-Fetal Medicine Committee, Society of Obstetricians and Gynaecologists of Canada
Members: Drs. Renato Natale (chairman),
chief, Department of Obstetrics and Gynaecology, St. Joseph's Health Centre. London, Ont.;
George Carson, director of perinatology, Regina General Hospital, Regina, Sask.; Duncan
Farquharson, acting head, Maternal-Fetal Medicine, Salvation Army Grace Hospital,
Vancouver, BC; Robert Liston, head, Department of Obstetrics, Grace Maternity Hospital,
Halifax, NS; Gérald Marquette, assistant professor of obstetrics and gynecology,
University of Montreal, Montreal, Que: and Patrick Mohide, professor of obstetrics and
gynecology, McMaster University, Hamilton, Ont.
Liaison: Dr. Alexander C. Allen
(CPS), head, Department Neonatal Pediatrics, Grace Maternity Hospital, Halifax, NS.
| Disclaimer: The recommendations in this position statement do not indicate an exclusive course of treatment or procedure to be followed. Variations, taking into account individual circumstances, may be appropriate. Internet addresses are current at time of publication. |